1. Field of the Invention
The present invention relates to compounds having an anion with a structure in which a perfluoroalkanesulfonyl group and another substituent are bonded to a nitrogen atom, and a method of manufacturing the same. Such a compound can be used, for example, as an electrolyte in any of various electrical storage devices.
2. Description of the Related Art
Bis(trifluoromethanesulfonyl)imide anion (−N(SO2CF3)2, hereinafter referred to as ‘TFSI’) is known as an anion able to form a salt that exhibits a liquid form in an ambient temperature range (hereinafter sometimes referred to as an ‘ambient temperature molten salt’ or an ‘ionic liquid’). A typical example of an ambient temperature molten salt having this anion is the salt between a 1-ethyl-3-methylimidazolium cation and TFSI.
In Japanese Patent Application Laid-open No. 2004-43407, ionic liquids comprising a compound having an anion with a structure in which two perfluoroalkanesulfonyl groups having different substituents are bonded to a nitrogen atom are described. Other technical documents relating to ionic liquids (ambient temperature molten salts) having an anion with a structure in which two perfluoroalkanesulfonyl groups are bonded to a nitrogen atom are Japanese Patent Application Laid-open No. 2003-243028 and Japanese Patent Application Laid-open No. 11-297355. Japanese Patent Application Laid-open No. 2003-201272 describes onium salts having an amide anion with a structure in which a perfluoroalkanesulfonyl group (e.g. SO2CF3) and a perfluoroalkanecarbonyl group (e.g. COCF3) are bonded to a nitrogen atom.
In Journal of Enzyme Inhibition Vol. 14 (1999) pp. 289-306, there is description relating to the synthesis of an N-cyanoperfluoroalkanesulfonamide (RSO2NHCN, wherein R is CF3, n-C4F9 or n-C8F17). For example, as a method of synthesizing N-cyanotrifluoromethanesulfonamide (CF3SO2NHCN), a method is described in which cyanamide and triflic acid anhydride (trifluoromethanesulfonic acid anhydride) are suspended in acetone, and triethylamine is instilled in. However, with this method, the triflic acid anhydride and the acetone solvent may react with one another. In actual fact, according to a re-examination carried out by the present inventors, the intended compound N-cyanotrifluoromethanesulfonamide could not be obtained using the above method.